Re: 2.6.24-rc4-git5: Reported regressions from 2.6.23

Rafael J. Wysocki
2007-12-08T21:52:58Z

On Saturday, 8 of December 2007, Andrew Morton wrote:
> On Sat, 8 Dec 2007 09:28:15 +0100 Ingo Molnar <mingo@elte.hu> wrote:
>
> >
> > * Fabio Comolli <fabio.comolli@gmail.com> wrote:
> >
> > > <snip>
> > >
> > > > Subject : Battery shows up twice in kpowersave
> > > > Submitter : Rolf Eike Beer <eike-kernel@sf-tec.de>
> > > > References : http://bugzilla.kernel.org/show_bug.cgi?id=9494
> > > > Handled-By : Alexey Starikovskiy <astarikovskiy@suse.de>
> > > > Patch :
> > > >
> > >
> > > I don't think that this is a regression: I reported on RedHat bugzilla
> > > when I switched from F7 to F8 and I was using 2.6.23.8 at that time.
> > > It looks to me an HAL regression, but of course I may be wrong :-) as
> > > the reported bisected to a bad commit.
> > >
> > > https://bugzilla.redhat.com/show_bug.cgi?id=373041
> > >
> > > By the way, I now switched to Fedrora Rawhide with a 2.6.24-rc4-git5
> > > custom kernel and Gnome desktop and the problem is still present, even
> > > with gnome-power-manager.
> >
> > to me this looks like an ABI regression - utilities should work without
> > change. Something changed in /sys output that caused HAL to think that
> > there are two batteries:
>
> Yep. Although HAL is of course a most special case of "userspace".
>
> > | The output of lshal shows that there are two UDI's with
> > | info.capabilities = { 'battery' }:
> > |
> > | udi = '/org/freedesktop/Hal/devices/acpi_BAT0'
> > | udi = '/org/freedesktop/Hal/devices/computer_power_supply_0'
> >
> > whether it's a HAL bug or a kernel bug, the original state should be
> > restored and it should be worked out without breaking users of older HAL
> > versions.
>
> "breaking users of older HAL versions" == "breaking machines".
>
> The patch should be reverted. Do we know which one it was?
>
> > grumble: way too many times do various system utilities break when i
> > upgrade the kernel on my laptop. Maybe a new debug mechanism: we should
> > start fingerprinting the exact /sys and /proc output and enforce that
> > it's immutable across kernel releases as long as the hardware is
> > unmodified?
>
> That would be neat. It would need to be executed on a lot of different
> machines.

Hm, that wouldn't allow us to add new attributes ...